Loose-leaf binder



May 9- T. RENGMANN LOOSE LEAF BINDER Filed April 21, 1928 if km 6 ki Patented May 7, 1929.

warren STATES THURE RENGMANN, OF BERLIN-CHARLOTTENBURG, GERMANY.

LOOSE-LEAF BINDER.

Application filed April 21, 1928, Serial 271,818,'and in Germany February 21, 1928.

This invention relates to a loose-loaf binder oi the kind wherein the leaves are threaded on arched, telescopically engaging prongs secured to hingedly connected carrying n1em bers which are normally prevented by stops from letting the prongs become disengaged.

One object 01. the invention is to provide readily operated means for releasing the earrying members when the prongs are to be separated, and the invention consists in this respect in the provision of a stop carried by a hand lever which is pivoted to the primary carrying member and which co-operates with a projection on thesecondary member for preventing normally a complete separation of the prongs, the lever being so arranged that while it is operated for releasing the car rying members from each other it can at the same time be used for raising the primary member into a position allowing the second ary member to be fully opened out. 7

Another object oi. the invention is to provide means for a convenient re-closing of the binder, and the invention consists in this respect in the provision on the primary carrying-member of a thumb-piece which is raised above the hinge of the secondary member as a support for a thumb while said secondary member is turned by one of the fingers into closed position. I l p The hand-lever and the thumb-piece are arranged close together so that, a change-over in the manipulation can be conveniently effected.

Fig. 1 of the accompanying drawings represents a side view showingby full lines the device in closed but raised position, and by dotted lines the tilted and open position,

Fig. 2, a front view of the device,

Fig. 3, a top view of the same, and I Fig. 4, a front view of a device of modi fied construction.

The binder comprises two sets of arched prongs which are connected to carrying members o and The carrying member 0 (herein called the primary member) is hinged at b to a plate a which is secured to the book cover. The carrying member 7 (herein called the secondary member) is hinged at e to the free end of the member 0. The prongs h connected to the member f are adapted to telescope within the tubular prongs (Z connected to the member 0. The prongs are arched concentrically with the hinge 0 about which the member 7 can be turned for separating the prongs in order to allow leaves to be added to or removed from the binder. When in closed position, the whole binder can be tilted about the hinge Z). To prevent, normally, a separation or the prongs, the carrying member 0 is provided with a stop a which cooperates with a projection is on the member The projection 71: is preferably pressed out of a semi-circular cheek-plate 2' whereby the carrying member is mounted on the hinge E. The stop allowsthe member 7'' to be turned relative to the member 0 to the position a in Fi g. 1, the'prongs being in this position extended as far as possible without complete separation. To allow the prongs to be separated, tile stop a must be retracted and it is for this purpose controlled by a springactuated hand'lever Z which is pivoted to the member 0 at m and formed with a. wide, milled finger-piece The lever Z is preferably bent like a bell-crank, as shown in Fi 2, so as to enable the stop a to move perpen+ dicularly to the plate 2' while the movement of the finger-pieceq is parallel to the member 0. When the binder is tilted back against the book-cover and is to beopened, it may be raised by means of the'lever [which is simultaneously depressed so as to allow the projection 79 to clear the stop n. The member f will then remain in the position b in Fig. 1, the prongs being separated.

In order to facilitate the closing of the binder, the primary member 0 is provided with an extension 0 and witha milled thumbpiece 39 which is carried by said extension above the hinge (2. With the thumb resting against the surface and with the fingers engaging the secondary member 7, thelatter can easily be turned about the hinge 6 into the closed position.

1 The two surfaces 29 and q are arranged close together so that a change-over in the manipulation can be conveniently effected.

There may be a stop 71. at each side of the binder in which case the two levers are preferably joined into a single resilient structure, as shown in Fig. 4:.

The extension 0 and the thumb-piece 29 may be carried by the lever Z instead of by the member 0 direct.

The binder may be provided with more than two sets of prongs.

I claim:

1. A loose-leaf binder of the character described, comprising a primary'prongcarrying member, a support to which said member is hinged, a secondary prong-carrying member hinged to the free end of said primary member, arched telescopically engaging prongs mounted on the two members so that the prongs can be separated by a deflection of the members about the connecting hinge, a projection on the secondary member, a pivotally supported, spring-controlled stop on the primary member co-operating with said pro ject-ion for preventing normally a complete separation of the prongs, and a hand lever whereby said stop can be actuated so as to clear the projection.

52. A device as claimed in claim 1 wherein the hand lever has the shape of a bell-crank.

3. The structure claimed in claim 1 in combination with a semi-circular cheek. plate which supports the secondary member on its hinge and which carries the projection.

4. The structure claimed in claim 1 in combination with an extension on the primary prong-carrying member, and a thumb-piece carried by said extension above the hinge which connects said primary member with the secondary member so as to enable the latter to be turned by means of a finger into closed position while the thumb rests against the thumb-piece.

5. The structure claimed in claim 1 in combination With two milled, closely situated finger-pieces, one. applied direct to the primary member for facilitating the closing of the binder, the other being applied to the hand lever as a means for depressing the latter and for turning the primary member about its hinge. V

6. A loose-leaf binder of the character described, comprising a primary prong-carrying member, a support to which said member is hinged, a secondary prong-carrying member hinged to the free end of the primary member, arched telescopically engaging prongs mounted on the two members so that the prongs can be separated by a deflection of the members about the connecting hinge, cheek-plates whereby said secondary member is supported on its hinge, projections pressed out of said cheek plate, pivoted stops carried by the primary member and adapted to co operate with said projections for preventing normally a complete separation of the prongs, and hand levers controlling said stops, the hand levers being connected so as to form a single resilient structure.

THURE RENGMANN; 

